Production of glutaric acid from 5-aminovaleric acid by robust whole-cell immobilized with polyvinyl alcohol and polyethylene glycol

In this study, we sought to enhance the stability and reusability of this whole-cell system for realizing the efficient production of glutaric acid under harsh reaction conditions. To this end, various matrices were screened to immobilize Escherichia coli whole-cell overexpressing 4-aminobutyrate aminotransferase (GabT), succinate semi-aldehyde dehydrogenase (GabD), and NAD(P)H oxidase (NOX). We ultimately selected a PVA-PEG gel (LentiKats®) for cell entrapment, and several factors of the reaction were optimized. The optimal temperature and pH were 35 °C and 8.5, respectively. Treatment with Tween 80 as a surfactant, as well as additional NOX, was found to be effective. Under the optimized conditions, an immobilized cell retained 55% of its initial activity even after the eighth cycle, achieving 995.2 mM accumulated glutaric acid, whereas free cell lost most of their activity after only two cycles. This optimized whole-cell system can be used in the large-scale production of glutaric acid.
Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research